This invention relates generally to the art of character generators, and more specifically concerns a character generator for a visual display device wherein the characters are produced from a plurality of stored binary words.
Graphics, in the form of cathode ray tube (CRT) displays, including characters, maps, and other visual representations, are being increasingly used to impart information to viewers. There is hence currently a significant emphasis on improving both (1) the quality of the graphics, especially the quality of characters, so that they may be more readily understood by the viewer, and (2) the speed of character generation, so that complete displays may be produced in minimum time.
Present systems generally suffer from two major disadvantages. First, those systems which are fast generally produce relatively poor quality characters, and vice versa. There is no presently known system which produces high quality characters at high speeds. Second, most character generators today use stored instructions to generate characters. These instructions are typically quite long, however, and hence consume a substantial amount of memory space, which is undesirable in most applications.
In view of the above, it is a general object of the present invention to overcome one or more of the disadvantages of the prior art mentioned above.
It is an object of the present invention to provide such an apparatus which produces high quality characters at speeds approaching or exceeding the fastest available generators.
A further object of the present invention is to provide such an apparatus wherein the stored instruction words use a minimum amount of memory space.
It is an additional object of the present invention to provide such an apparatus which is capable of running at a fast constant frequency.
It is a still further object of the present invention to provide such an apparatus which is capable of changing character size without adding memory space.
It is yet another object of the present invention to provide such an apparatus which is capable of rotating a character.